Hi James, good to hear from you!
Our current thinking is that ISO 8601 is in error and we want to request
a change disallowing the year 0000.
You said:
> Now the year 1BC in the proleptic Gregorian calendar is a leap year.
Where can I confirm this information? We've been worrying about a
related change in the comparison of durations that is affected by this
information.
All the best, Ashok
===========================================================
-----Original Message-----
From: James Clark [mailto:jjc@jclark.com]
Sent: Tuesday, April 23, 2002 6:30 AM
To: www-xml-schema-comments@w3.org
Subject: Internal inconsistency wrt year 0000
The inconsistency between XML Schema Part 2 and ISO 8601:2000 wrt year
0000
has already been commented on, but there is also a minor internal
inconsistency. XML Schema Part 2 disallows year 0000, which means that
year -0001 corresponds to 1BC (whereas in ISO 8601:2000, 1BC is year
0000).
Now the year 1BC in the proleptic Gregorian calendar is a leap year.
However, appendix E uses the formula
modulo(Y, 400) = 0 OR (modulo(Y, 100) != 0) AND modulo(Y, 4) = 0
to determine whether Y is a leap year. But this formula makes year
-0001
not a leap year. If year 0000 was allowed (representing 1BC), then the
formula would be correct.
James